1. Field of the Invention
The present invention relates to a breaker device used for changing over a power cable connected to a battery of an automobile between a state of continuity and a state of non-continuity.
2. Description of the Related Art
According to Japanese Patent Application No. 10-47920 applied by the present applicant, there is disclosed a structure in which the breaker device 1 and the fuse 4 are separately arranged in the middle of a power cable of an electric automobile as shown in FIG. 16.
On the other hand, according to Japanese Unexamined Patent Publication No. 9-223439, there is disclosed a structure in which the fuse 4 is accommodated in the breaker device 3 as shown in FIG. 17. In this breaker device 3, the fuse 4 is accommodated in the case body 5A, and two columnar electrodes 2, 2 rise from the bottom face of the case body 5A. On the cover 5B which covers an upper face open portion of the case body 5A, there are provided a pair of holes 6, 6 corresponding to the stationary electrodes 2, 2. When both cylindrical legs 8, 8 provided in the movable electrode 7 are inserted into these holes 6, 6, both the stationary electrodes 2, 2 and both the legs 8, 8 are engaged with each other, so that both the stationary electrodes 2, 2 can be electrically communicated with each other. Therefore, electrical wire xe2x80x9cexe2x80x9d can be changed over from a state of non-continuity to a state of continuity.
In this connection, both the breaker devices 1, 3 described above have both advantages and disadvantages. Concerning the breaker device 1 shown in FIG. 16, the breaker device 1 is provided separately from the fuse 4. Therefore, the breaker device 1 shown in FIG. 16 is advantageous in that it is possible to reduce the size compared with a breaker device in which the breaker device and the fuse are integrated with each other into one body. However, this breaker device 1 shown in FIG. 16 is disadvantageous as follows. The fuse 4 can be exposed under the condition that the breaker device 1 is turned on. Therefore, for example, when an operator touches the fuse in the case of replacing the fuse, it is necessary for him to make sure that the breaker device 1 has already been turned off, that is, it is necessary for the operator to pay close attention to the fuse.
On the other hand, concerning the latter breaker device shown in FIG. 17, it is impossible to replace the fuse unless the movable electrode is disconnected and the breaker device 3 is turned off. Therefore, this breaker device is advantageous in that the breaker device 3 is necessarily turned off in the case of replacing the fuse. However, the breaker device 3 is composed in such a manner that the stationary electrodes 2, 2 are separately raised. Therefore, it is difficult to reduce the size of the breaker device. Further, since the movable electrode 7 and the stationary electrode 2 are connected with each other, the movable electrode must penetrate the cover 5B at two positions, which deteriorates the operation property.
Moreover, when the size of the breaker device is reduced, in order to enhance the reliability of contact of the stationary electrode with the movable electrode, it is necessary to ensure the contact pressure of the stationary electrode with the movable electrode.
The present invention has been accomplished in view of the above circumstances. It is an object of the present invention to provide a breaker device, the sizes of which is reduced, the contact pressure of the stationary electrode with the movable electrode of which can be ensured sufficiently high.
A first aspect of the invention provides a breaker device comprising: a pair of sheet-shaped stationary electrodes arranged on a front and a rear side of a protruding wall rising from a breaker body; a recess-shaped plug to be attached to the protruding wall; and a movable electrode arranged in a recess of the plug into which the protruding wall proceeds, the movable electrode including a first and a second pinching piece respectively coming into contact with the stationary electrodes, the base end portions of which are connected with each other by a continuity section, wherein the continuity section rises from the base end portion of the first pinching piece toward the second pinching piece, and the continuity section on the second pinching piece side is gently curved so that it continues to the second pinching piece.
In the structure described in the first aspect of the invention, the pair of stationary electrodes are arranged on the front and the rear side of the protruding wall, that is, the pair of stationary electrodes are collected at one place. Therefore, the pair of stationary electrodes have a space round both the stationary electrodes in common. Accordingly, the size of the breaker device can be reduced. When the plug is attached to the protruding wall, the protruding wall is interposed between the first and the second pinching piece of the movable electrode accommodated in the plug, and each stationary electrode comes into contact with each pinching piece. In this case, it is enough that the plug is attached at one position. Therefore, compared with the conventional structure in which the plug is attached at two positions, the attaching work of the plug of this structure can be made simple.
In this connection, when the plug is attached to the protruding wall, both the pinching pieces are expanded by the protruding wall. As a specific example is shown in FIG. 10A, the continuity section for connecting both the pinching pieces rises from the base end portion of the first pinching piece (K1), and the continuity section on the second pinching piece (K2) side curves gently and continues to the second pinching piece (K2). Therefore, as a comparative structure is shown in FIG. 10B, compared with the structure in which the continuity section is symmetrically formed and the pinching pieces (K1, K2) are connected with each other, the radius of curvature of the continuity section in the structure of the present invention is decreased (shown by marks r1, r2 in the drawing). Accordingly, concentration of stress caused in the continuity section can be relieved. Due to the foregoing, pinching forces of both the pinching pieces can be increased. Accordingly, the contact pressure between the movable electrode and the stationary electrode can be ensured sufficiently high.
A second aspect of the invention provides a breaker device, wherein the recess in the plug is formed in such a manner that the inside of the recess is larger than the opening, end portions of the first and the second pinching piece of the moveable electrode come into contact with the opening edge of the recess when the first and the second pinching piece are in the natural condition so that the movable electrode can not be drawn out from the recess. Accordingly, it is possible to prevent the movable electrode from coming off.
A third aspect of the invention provides a breaker device, wherein a portion of the peripheral wall of the recess of the plug is formed and incorporated into the peripheral wall differently from other portions of the peripheral wall, and the movable electrode is capable of being accommodated into the recess from a portion into which the portion of the peripheral wall is incorporated.
A fourth aspect of the invention provides a breaker device comprising: a protruding wall rising from a base section of a breaker body; a pair of sheet-shaped stationary electrodes arranged on a front and a rear side of the protruding wall; a recess-shaped plug to be attached to the protruding wall; a U-shaped movable electrode accommodated in the plug, electrically communicating both the stationary electrodes by pinching the protruding wall from the front and the reverse face; a fuse accommodating section arranged inside a surrounding wall rising from the base section in parallel with the protruding wall, accommodating a fuse connected with one of the stationary electrodes; a cover covering an open face of the fuse accommodating section, capable of being engaged with the a surrounding wall; an engaging face formed in the plug, directed to the front of the attaching direction of the plug; and a cover movement restricting section provided on the cover, engaged with the engaging face of the cover under the condition that the cover is engaged with the protruding wall.
In the structure of the fourth aspect of the invention, a pair of stationary electrodes are arranged on the front and the rear side of the protruding wall, that is, a pair of stationary electrodes are collected at one place. Therefore, the pair of stationary electrodes have a space round both the stationary electrodes in common. Accordingly, the size of the breaker device can be reduced. When the plug is attached to the protruding wall, the protruding wall is pinched by the movable electrode accommodated in the plug. Therefore, both the stationary electrodes are electrically communicated with each other. In this case, it is enough that the plug is attached at one position. Therefore, compared with the conventional structure in which the plug is attached at two position, the attaching work of the plug of this structure can be made simple. In this connection, when the plug is attached to the protruding wall, the cover movement restricting section provided on the cover which covers the fuse accommodating section engages with the engaging face provided in the plug. Accordingly, unless the plug is pulled out, the cover can not be removed. In other words, when the fuse is replaced, the plug is necessarily disconnected and a state of non-continuity can be obtained.
A fifth aspect of the invention provides a breaker device, wherein the engaging face is arranged on the forward end side of the attaching direction of the plug, the cover movement restricting section is arranged at a lower end of a vertical wall extending downward along a side of the plug from a ceiling portion of the cover, and the cover movement restricting section is formed into a protruding piece protruding from the lower end of the vertical wall so that the cover movement restricting section is arranged along the engaging face of the plug.
According to the fifth aspect of the invention, the cover movement restricting section engages with the engaging face arranged on the forward end side of the plug in the attaching direction. Therefore, when the plug is disconnected halfway from the protruding wall, the cover movement restricting sections still engages with the engaging face, and the cover can not be disengaged from the fuse accommodating section. That is, unless the plug is completely disconnected from the protruding wall and the fuse is set in a state of complete non-continuity, the cover can not be disengaged from the fuse accommodating sections, and it becomes possible to prevent the fuse from being replaced in a state of continuity.
A sixth aspect of the invention provides a breaker device, wherein an engaging section to be engaged with the surrounding wall so as to restrict the cover from being disengaged is provided on the cover on a side distant from the plug.
According to the sixth aspect of the invention, both end portions of the cover are engaged with the engaging face of the plug and the engaging section of the surrounding wall of the breaker body. Therefore, it is possible to prevent the cover from being obliquely disengaged.
A seventh aspect of the invention provides a breaker device comprises: a pair of sheet-shaped stationary electrodes arranged on a front and a rear side of a protruding wall rising from a breaker body; and a portal-shaped movable electrode capable of short-circuiting the stationary electrodes, wherein when the movable electrode is attached to the protruding wall, lower end portions of a pair of leg pieces provided in the movable electrode, the interval of which is shortened, respectively come into contact with the stationary electrodes so that both the stationary electrodes can be changed over from a state of non-continuity to a state of continuity, and the protruding wall includes a lance extending downward from an upper end of the protruding wall in a cantilever-shape and preventing the stationary electrode from coming off when the lance is butted against a forward end face of the stationary electrode and the protruding wall also includes lance protection walls arranged adjacent to the lance on the protruding wall, for opening the leg pieces so that the leg pieces can not be contacted with the lance when the lower end portions of the leg pieces passes through the forward end side of the protruding wall.
In the breaker device according to an eighth aspect of the invention, the lance protection walls are formed into a pair, and the lance is arranged between both lance protection walls being formed into a pair.
According to the invention, a pair of stationary electrodes are arranged on the front and the reverse face of the protruding wall so as to collect the stationary electrodes. Therefore, the pair of stationary electrodes have a space round both the stationary electrodes in common. Accordingly, the size of the breaker device can be reduced. Since the stationary electrodes are prevented from coming off by the lances, there is no possibility that the stationary electrodes are pulled out upward by a friction force generated when the movable electrode is pulled out. Further, when the stationary electrode is incorporated being moved from the upper end side to the base end side of the protruding wall, the lance is pushed in the middle of movement by the stationary electrode and retracted from the path of the stationary electrode. Therefore, no lance obstructs the movement of the stationary electrode. Accordingly, the stationary electrode can be easily incorporated. Further, when the movable electrode is attached to and detached from the protruding wall, the lower end portions of the legs provided in the movable electrode are opened by the lance protection walls provided adjacent to the lances so that the lance can not be contacted with the movable electrode. Therefore, when the movable electrode is attached to and detached from the protruding wall, the lance is not deformed, and the stationary electrode can be stably held.
Concerning the lower end portions of the leg pieces provided in the movable electrode, both end portions in the width direction are held by a pair of lance protection walls in such a manner that both end portions are supported. Therefore, the leg pieces of the movable electrode can be positively prevented from coming into contact with the lances. Further, the lances are formed into a pair and butted against both side sections of the end of the stationary electrode. Therefore, they are positively prevented from coming off. Furthermore, compared with a case in which one wide lance is provided, the lance deformation reaction force can be suppressed.